The present invention relates to a braking device particularly usable for skates including a shoe composed of a quarter articulated to a shell which is in turn associated with a supporting frame for two or more wheels.
Currently, in conventional roller skates, whether constituted by a shoe associated with a support for two pairs of mutually parallel wheels or by a shoe associated with a supporting frame for two or more in-line wheels, there is the problem of braking said wheels to adjust the speed of the skate.
It is known to use adapted blocks or pads, usually made of rubber, which are arranged at the toe or heel region of the shoe. When the user tilts the shoe forwards or backwards, the free end of the blocks or pads interacts with the ground and braking is thus achieved.
However, the operation of conventional brakes is not satisfactory because they require the user to rotate the shoe, and thus the frame associated therewith, at the toe or heel, and this can cause loss of balance with consequent falls.
U.S. Pat. No. 1,402,010 discloses a roller skate having a strap that can be secured on the user's leg above the malleolar region, a rod being connected to the strap.
The rod surrounds the leg to the rear and is then curved so as to laterally affect the leg until it is associated at its ends, in the malleolar region, with a lever system which is articulated to a structure protruding from the wheel supporting frame.
The lever system protrudes to the rear of the frame and is connected to a plate which is shaped approximately complementarily to the curvature of part of an underlying and facing wheel.
This solution is not free from drawbacks: first of all, a relative movement between the strap and the leg is produced during sports practice, and this does not make its use comfortable due to the continuous rubbing of the strap on the leg.
Furthermore, the plate is activated every time the user bends his leg backwards beyond a given angle, with no true and easy possibilities to vary this condition.
Since the shape of the leg is different for each user for the same rod length there is a different braking action at different rotation angles.
Furthermore, the rod acts and presses in the malleolar region, and this can cause discomfort or accidental impacts. Finally, the wheel wears out considerably.
U.S. Pat. No. 4,275,895 provides a partial solution to this drawback, and illustrates a brake for skates with two pairs of mutually parallel wheels which acts at the rear wheels.
The brake is constituted by a tongue which is associated with the shoe in a rearward region. A plate is associated with the tongue in a rearward position and is pivoted at the frame that supports the shoe.
At its free end, the plate has a transverse element on which a pair of C-shaped elements is formed at the lateral ends. Following a backward rotation imparted to the tongue, the C-shaped elements interact with the rear wheels facing them, so as to interact with their rolling surface.
Even this solution, however, has drawbacks: it is in fact structurally complicated and therefore difficult to industrialize. It also entails the presence of adapted springs that allow the tongue to return to the position in which the pair of C-shaped elements does not interact with the wheels, and this further increases structural complexity.
Furthermore, the structural configuration of the brake causes the pair of C-shaped elements to interact with the wheel even upon a minimal backward rotation imparted to the flap and therefore even for involuntary movements, and this produces unwanted braking actions and thus possible loss of balance or lack of coordination.
Finally, interaction of the C-shaped element at the rolling surface of the wheels leads to rapid wheel wear and thus to non-optimum rolling which necessarily entails continuous replacement of the wheels.
U.S. Pat. No. 4,300,781 discloses a braking device for skates that comprise pairs of mutually parallel wheels.
A brake is thus comprised which is constituted by a plate that is transversely pivoted at the rear end of the frame that supports a shoe; pads are associated with the ends of said plate and face the rolling surface of the rear pair of wheels.
The brake is activated by using a cable which is suitable to rotate the plate, in contrast with a spring associated with the support for the pair of front wheels, so as to move the pads into contact with the rolling surface of the pair of rear wheels.
This cable can be activated by means of rings or handles associated with a strap which can be arranged on the user's legs by virtue of the presence of temporary connection means.
However, this solution has considerable drawbacks: first of all, the brake activation can lead to possible loss of balance, as the user does not assume, with his body, a position suitable to control the sudden speed reduction; only the hand of the skater is in fact involved in the brake activation.
Furthermore, as sports practice can occur while wearing trousers, when the rings are pulled the strap may slip along the trousers or pull them so that they slide along the leg, hindering the braking action.
Finally, there is a loose cable which, besides being a hindrance to the skater, can accidentally catch during skating, especially since coordination of the arm-legs movement places the legs rhythmically laterally outwards.